perf tools: Add machine__module_dso function

perf tools: Add machine__module_dso function

Separate the dso object addition and update when adding new kernel
module.

Currently we update dso's symtab_type any time we find it in the list,
because we can't distinguish between new and found dso from
__dsos__findnew function.

Adding machine__module_dso that separates finding and adding new dso
objects, so there's no superfluous update of dso.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-uvqgs5tyq4wssnq6fm43hgvk@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>